[clang] [HLSL] Overloads for `lerp` with a scalar weight (PR #137877)

[Justin Bogner via cfe-commits]

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@@ -277,6 +277,12 @@ constexpr bool4 isinf(double4 V) { return isinf((float4)V); }
 // lerp builtins overloads
 //===----------------------------------------------------------------------===//
 
+template <typename T, uint N>
+constexpr __detail::enable_if_t<(N > 1 && N <= 4), vector<T, N>>
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bogner wrote:

I also think it feels a bit odd, but I was following the examples from [clamp](https://github.com/llvm/llvm-project/issues#128230) and [min/max](https://github.com/llvm/llvm-project/issues#128231). I think if we're going to move them, we should do all of these together.

https://github.com/llvm/llvm-project/pull/137877